The early development of the mouse lens is being studied in normal embryos and in embryos of mouse strains which show genetic abnormalities of the lens (aphakia; Cataract-Fraser; lens rupture; eye-less). The emphasis of the research is on morphological and biochemical changes that accompany the earliest phase of lens formation from the ectoderm (the period of lens "induction"). Areas of particular concern are specific protein synthesis (studied mainly by immunochemical means), cell proliferation (studied by autoradiography) and ultrastructure. It is hoped that these studies will lead to better understanding of the genetic regulation of lens differentiation and of the pathogenesis of genetic eye defects. BIBLIOGRAPHIC REFERENCES: Zwaan, J. (l975) Immunofluorescent studies on aphakia, a mutation of a gene involved in the control of lens differentiation in the mouse embryo. Develop. Biol. 44, 306-312. Hendrix, R.W. and Zwaan, J. (l975) The matrix of the optic vesicle-presumptive lens interface during induction of the lens in the chicken embryo. J. Embryol. Exp. Morphol. 33, 1023-1049.